title: High spatial and temporal resolution dynamic contrast-enhanced magnetic resonance angiography using compressed sensing with magnitude image subtraction.
abstract: OBJECTIVE
  We propose a compressed-sensing (CS) technique based on magnitude image subtraction for high spatial and temporal resolution dynamic contrast-enhanced MR angiography (CE-MRA).
  
  
  METHODS
  Our technique integrates the magnitude difference image into the CS reconstruction to promote subtraction sparsity. Fully sampled Cartesian 3D CE-MRA datasets from 6 volunteers were retrospectively under-sampled and three reconstruction strategies were evaluated: k-space subtraction CS, independent CS, and magnitude subtraction CS. The techniques were compared in image quality (vessel delineation, image artifacts, and noise) and image reconstruction error. Our CS technique was further tested on seven volunteers using a prospectively under-sampled CE-MRA sequence.
  
  
  RESULTS
  Compared with k-space subtraction and independent CS, our magnitude subtraction CS provides significantly better vessel delineation and less noise at 4× acceleration, and significantly less reconstruction error at 4× and 8× (P < 0.05 for all). On a 1-4 point image quality scale in vessel delineation, our technique scored 3.8 ± 0.4 at 4×, 2.8 ± 0.4 at 8×, and 2.3 ± 0.6 at 12× acceleration. Using our CS sequence at 12× acceleration, we were able to acquire dynamic CE-MRA with higher spatial and temporal resolution than current clinical TWIST protocol while maintaining comparable image quality (2.8 ± 0.5 vs. 3.0 ± 0.4, P = NS).
  
  
  CONCLUSIONS
  Our technique is promising for dynamic CE-MRA.
authors.affiliation: Department of Radiological Sciences, David Geffen School of Medicine, University of California, Los Angeles, California, USA.
authors.forename: Stanislas
authors.initials: S
authors.lastname: Rapacchi
authors.forename: Fei
authors.initials: F
authors.lastname: Han
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Natsuaki
authors.forename: Randall
authors.initials: R
authors.lastname: Kroeker
authors.forename: Adam
authors.initials: A
authors.lastname: Plotnik
authors.forename: Evan
authors.initials: E
authors.lastname: Lehrman
authors.forename: James
authors.initials: J
authors.lastname: Sayre
authors.forename: Gerhard
authors.initials: G
authors.lastname: Laub
authors.forename: J Paul
authors.initials: JP
authors.lastname: Finn
authors.forename: Peng
authors.initials: P
authors.lastname: Hu
mesh_terms: D000465:Algorithms; D001158:Arteries / Q000033:anatomy & histology / Q000502:physiology*; D001783:Blood Flow Velocity / Q000502:physiology; D003287:Contrast Media; D044962:Data Compression / Q000379:methods*; D005682:Gadolinium; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D018810:Magnetic Resonance Angiography / Q000379:methods*; D009942:Organometallic Compounds; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013382:Subtraction Technique
chemical_list: D003287:Contrast Media; D009942:Organometallic Compounds; D005682:Gadolinium; C109932:gadofosveset trisodium
keywords: DCE-MRI; background suppression; compressed sensing; dynamic contrast-enhanced MRI; magnetic resonance angiography